Carrier Aggregation Research Articles

Cross-Tier Interference Mitigation in 3D HetNets for LTE and Wi-Fi Access

Due to the unprecedented rate of transformation in the field of wireless communication industry, there is a need to prioritise the coverage, network power and throughput as preconditions. In Heterogeneous Networks (HetNets) the low power node inclusion like Femto and Pico cells creates a network of Multi-Tier (M-Tier) which is regarded as the most significant strategy for enhancing the coverage, throughput, 4G Long Term Evolution (LTE) ability. This work mainly focuses on M-Tier 3D Heterogeneous Networks Energy Efficiency (EE) based Carrier Aggregation (CA) scheme for streaming real-time huge data like images. At first, M-Tier 3D HetNets scheme was made for investigating Signal to Noise Interference Ratio (SNIR) on assessing the collective Pico-tier and Femto-tier interference. Next, the scheme of channel allocation is scrutinised so as to estimate throughput from the multiple tiers. Additionally, with the use of CA technique, the problem of energy efficiency for M-Tier 3D Heterogeneous Network (HetNet) in relation to energy metrics and throughput was evaluated with the use of LTE and Wireless Fidelity (Wi-Fi) coexistence. The simulation is carried out in a MATLAB setting, and the outcomes reveal a huge impact on EE. The simulation is carried in terms of EE, transmission time, throughput, packet success rate, convergence probability, and coverage region. The analysis from simulation shows that on improving the output of the device, interference among small cell base stations is reduced on increasing EE. The outcomes attained aid in the effective creation of M-Tier 3D HetNets for enhancing EE by employing Multi-Stream Carrier Aggregation (MSCA) in HetNets.

AI-Enabled Energy-Aware Carrier Aggregation in 5G New Radio With Dual Connectivity

AI-Enabled Energy-Aware Carrier Aggregation in 5G New Radio With Dual Connectivity

LTE & 5G NR Carrier Aggregation Network Optimization through Advanced Measurement Configuration

LTE & 5G NR Carrier Aggregation Network Optimization through Advanced Measurement Configuration

CA Energy Saving Joint Resource Optimization Scheme Based on 5G Channel Information Prediction of Machine Learning

Carrier aggregation (CA) is considered as a key enabling technology to provide higher rates for users in LTE/5G networks. However, the increased transmission rate is accompanied by higher energy consumption. The existing CA energy efficiency resource optimization allocation scheme in 5G does not fully consider the following two issues, namely, the impact of delayed channel state information feedback on the rationality of resource allocation and the increasing in energy consumption caused by frequent switching of component carriers (CCs) by narrowband users; this paper proposed a CA energy-efficient joint resource optimization allocation (PEJA) scheme based on channel information prediction. The proposed scheme (PEJA) fully considers the above two issues. Firstly, the algorithm of random forest predicting channel state information is designed. On the basis, the CA energy-efficient joint resource optimization allocation (PEJA) scheme based on channel information prediction is proposed. The simulation results show that the proposed algorithm PEJA has a higher energy efficiency and throughput than the comparison algorithm under different numbers of users and different transmission powers. The PEJA algorithm is more energy efficient than the PEJA-NC algorithm, which does not consider the CC handover of narrowband users. To sum up, the proposed PEJA energy-efficient resource allocation scheme maximizes system energy efficiency and achieves a higher throughput.

Technologies Used In 5G Antennas (Comprehensive Review)

In this review, we will shed light on the technology of antennas used in communication within the fifth generation, and we will elaborate on two types of this most advanced technology. The first is Compact Wide-Band Microstrip Patch Antenna; the second type is Four Elements MIMO Antenna. The world has become a network of interconnected networks, and this communication has resulted in huge and enormous data, and the world of communications has become crowded with transmitted and received data, and this development requires revolutions. In the world of wireless communications until we have now reached the world of the fifth generation and the world of augmented virtual reality, and what it requires to connect what affects human life from the home to the car to the workplace, and in parallel with the revolutions in the world of applications, a revolution occurred in the world of antennas, which is the means through which data is transmitted. While doing a review of 5G antennas, The MIMO antennas are the best candidate for smartphones while the massive MIMO antennas can be used at base stations. In MIMO metal rim antenna design the use of carrier aggregation reinforces transmission rate. Also, design features like orthogonal polarization boost isolation thereby enhancing the overall efficiency.

Feedback-based algorithm for aerial cell's trajectory using deep learning for efficient performance in 6G

Sixth (6th) Generation (6G) wireless communication proposes Non-Terrestrial aerial Network (NTN) architecture to support dynamic scaling of both coverage and capacity. In this paper, we discuss Low Altitude Platform (LAP) based aerial cell for NTN which augments the terrestrial cell through Dual Connectivity (DC) or Carrier Aggregation (CA) on an independent and non-interfering frequency carrier. The determination of an optimal trajectory for a LAP based aerial cell is critical in the deployment for improving its resource utilization within the given flight time. The available literature on selecting trajectory for drone cell have independently considered the data traffic requirements or the mobility of the User Equipment (UE) while improving the throughput or coverage respectively. We propose for the first time; a novel Zone-based Drone Positioning and Trajectory algorithm for selecting UEs to be served by a drone cell as well as for choosing the position and trajectory of the LAP based aerial cell. The proposed algorithm utilizes a new feedback quantity from the UE called Feedback for Aerial Cell Trajectory (FACT), which contains UE's predicted data traffic, traffic preference, and mobility state. The algorithm and FACT are presented mathematically with a combination of closed-form equations with a deep learning (Long Short-Term Memory (LSTM)) model and evaluated through extensive simulations. The simulation shows improvement by 44% in spectrum resource utilization of an aerial cell and a 27% improvement in user throughput over available schemes in the literature.

Synergistic passivation and stepped-dimensional perovskite analogs enable high-efficiency near-infrared light-emitting diodes

Formamidinium lead iodide (FAPbI3) perovskites are promising emitters for near-infrared light-emitting diodes. However, their performance is still limited by defect-assisted nonradiative recombination and band offset-induced carrier aggregation at the interface. Herein, we introduce a couple of cadmium salts with acetate or halide anion into the FAPbI3 perovskite precursors to synergistically passivate the material defects and optimize the device band structure. Particularly, the perovskite analogs, containing zero-dimensional formamidinium cadmium iodide, one-dimensional δ-FAPbI3, two-dimensional FA2FAn-1PbnI3n+1, and three-dimensional α-FAPbI3, can be obtained in one pot and play a pivotal and positive role in energy transfer in the formamidinium iodide-rich lead-based perovskite films. As a result, the near-infrared FAPbI3-based devices deliver a maximum external quantum efficiency of 24.1% together with substantially improved operational stability. Combining our findings on defect passivation and energy transfer, we also achieve near-infrared light communication with device twins of light emitting and unprecedented self-driven detection.

(Electrodeposition Division Research Award) Impact of Electrodeposition on the Design and Synthesis of Nanoporous Functional Materials

The sustainable growth of efficient and durable functional nanomaterials applicable in a variety of practical fields is founded on the creative design, rational synthesis, extensive characterization, and realistic testing of products developed by countless hard-working research teams. Many of these nanomaterials must include high-cost and scarcely distributed elements and compounds that need to be either eliminated or minimally used as much as it is possible. Most commonly, such minimization has been approached by synthesizing the materials of interest in the form of nanoparticles. Nanoparticles are undoubtedly superior to other type of materials in a variety of fields and applications because of their large surface area to volume ratio and unique chemical and physical properties. Their implementation in practice also addresses well the objective for minimization of the use of expensive elements and compounds. At the same time, as class of nanomaterilas, the nanopartiles suffer some drawbacks like loss of material during synthesis, surface contamination/blockage by chemicals used in their synthesis, mechanical disconnection from carrier electrodes, and / or aggregation during exploitation. Such unwelcome developments often make it difficult to keep the cost low and/or lead to a reduction of the active surface area and thus, to loss of functionality, performance, and stability.A way of addressing some of the mentioned shortcomings is to employ electrochemical approaches for synthesizing alternative nanostructured materials directly on the carrier electrode. Such approach not only provides for better adhesion and contamination free surface, but also enables an efficient control of the amount of the deposited material along with flexibility in the structuring during the material synthesis, thus most-certainly reducing its overall cost of the final product. The electrochemical means inevitably include controlled electrodeposition of a binary / ternary alloy layer with a desired thickness and pre-selected elemental composition. A naturally following step in the material's synthesis is the selective oxidative dissolution of the less / least noble metal (a.k.a. de-alloying) to create a continuous nanoporous film with tunable pore and ligament size comprising a length-scale in the single-digit nanometer range. Finally, as-synthesized nanostructured films may either be employed directly for the purposes of the intended applications or be subjected to an additional surface functionalization by a further electrodeposition or electroless of a thin layer with specific properties that is aimed at boosting the material's functionality, performance and stability.This talk will introduce the use of electrochemical means in the design and synthesis of continuous nanoporous Au- and Cu-based functional alloy nanomaterials with applications in electrocatalysis, environmental protection, and electronic packaging. The discussed synthetic approaches will include bulk alloy electrodeposition, electrochemical de-alloying, and electrochemical atomic layer deposition for surface functionalization by films with a thickness in the range from a sub-monolayer to a few monolayers. The presentation of each class of nanostructured materials of interest to this talk will include a conceptual description of their synthetic routines, followed by an electrochemical and ultra-high vacuum-based characterization results, and concluded with a glimpse into the outcome of standard performance tests of the functionality, performance, and stability of said materials in intended applications. Finally, aspects of the materials performance associated with hypothesized mechanistic views will be critically discussed in comparison with other nanoparticulate and/or nanostructured counterpart materials in the literature.

Delay-Aware and Energy-Efficient Carrier Aggregation in 5G Using Double Deep Q-Networks

As one of the key technologies in 5G networks, Carrier Aggregation (CA) is studied in this paper. In CA, Component Carriers (CCs) can be activated and deactivated depending on multiple factors, e.g., energy consumption and Quality of Service (QoS) demand of users. We propose CC management strategies where each User Equipment (UE) minimizes its average delay and at the same time minimizes its power consumption while considering that CCs can be activated and deactivated only at certain times, as in real-world CA implementations. We first model the problem as a centralized multi-objective optimum CC management problem. Since centralized approaches would impose a large overhead on the system, we then develop a semi-distributed solution by modeling the problem as a stochastic game and propose a multi-agent Double Deep Q-Network (DDQN) based CC management algorithm to solve the stochastic game. We finally compare the proposed approaches with single CC activation and all-CC activation baseline schemes. Simulation results show that our proposed algorithms outperform the all-CC algorithm in terms of UE power consumption and have the capability of transmitting a number of bits with delay close to the all-CC scheme. Meanwhile, our DDQN-based algorithm decreases the UE power consumption by about 20% with respect to the all-CC scheme.

A new fair-efficient spectrum allocation scheme for the LTE and WiFi coexistence platform

Long-term evolution (LTE) carrier aggregation with the unlicensed WiFi spectrum band has been pointed out as a good solution to handle the rapidly increasing wireless data traffic amounts. With both LTE and WiFi networks, the investigation of their coexistence is a hot research topic of active interest, primarily driven by industry and academia. In this study, we investigate a new spectrum allocation scheme for the LTE/WiFi coexistence platform. To maximize the system throughput while guaranteeing a relative fairness between heterogeneous networks, we adopt the cooperative game paradigm to design our novel scheme. According to the basic ideas of Proportional Nash bargaining solution (PNBS) and Zhang’s group bargaining solution (ZGBS), we can leverage a mutual consensus to provide a fair-efficient solution for the LTE/WiFi spectrum sharing problem. Based on the online interactive bargaining approach, network agents work together to effectively share the LTE and WiFi spectrum resources. Under dynamically changing network environments, it is an essential approach to find the relevant trade-off between conflicting requirements, i.e., fairness and efficiency. Validated by simulation results, our proposed scheme can provide important insights into the LTE/WiFi system operations. Finally, we forecast further research trends on the basis of our conclusion.

Coverage Analysis and Chance-Constrained Optimization for HSR Communications With Carrier Aggregation

This paper investigates coverage analysis and performance optimization for a high-speed railway (HSR) communication system with carrier aggregation (CA). Initially, the system model is established. By using CA technology, the statistical characteristic of the received signal-to-noise ratio (SNR) is obtained. Then, for the systems with or without CA, unified theoretical expressions for the edge coverage probability (ECP) and the percentage of cell coverage area (CCA) are obtained, respectively. After that, a chance-constrained coverage optimization is proposed to improve the coverage performance, which is effectively solved by using a heuristic algorithm. Numerical results show that the derived expressions of the ECP and the percentage of CCA are accurate and can be directly used to evaluate the coverage performance without time-intensive simulations. Moreover, the impacts of CA, transmit power, cell radius, received SNR threshold, HSR scenario on coverage performance have been discussed. Furthermore, the effectiveness of the proposed coverage optimization scheme is also verified.

The Evaluation of the Throughput Performance of an LTE-Advanced Urban Area Network with the Inter-Band Non-Contiguous Carrier Aggregation Method

Data obtained from the drive-test in the urban area (a case study of Siliwangi Stadium, Bandung) revealed that the low throughput occurred on the downlink, which was 3.56 Mbps. On the uplink, it was 20.7 Mbps. Additionally, based on the Operating Support System (OSS) data, the site had high resource block usage (80% of PRB usage). It revealed the high traffic volume in the area, which resulted in poor throughput values received by users. The area is one of the potential market areas in the city of Bandung, which is indicated by housing, military area command education and training regiment, schools, hotels, markets, and stadiums. Based on the Site Database (SDB), it was known that the site has not yet implemented the carrier aggregation method. This study evaluated throughput using the Inter-Band Non-Contiguous Carrier Aggregation method by comparing three scenarios: Non-CA, CA Non-Repeater, and CA Repeater. Based on the results of the non-CA simulation, the downlink throughput increased by 23,582 Mbps, and the uplink throughput by 20.098 Mbps. Meanwhile, in the non-repeater CA simulation, the downlink throughput increased by 44.56% to 34.091 Mbps, and the uplink throughput increased by 39.22% to 27.980 Mbps. Furthermore, the CA Repeater simulation increased downlink throughput by 63.70% to 38.603 Mbps and uplink throughput by 45.06% to 29.154 Mbps.

Assessing the Barriers Towards the Glocalization of India’s Mobile Industry: An IVIFs-DEMATEL with Choquet Integral Method

Although mobile brands from various countries have taken to the global market, some brands are left to be GLOCALised (local to global). The nonGLOCALisation of these brands are due to some unseen hindrances. This paper is unique in its aim to analyze the challenges faced by local mobile phone supply chains (MPSC) from entering the global market in an Indian context. We analyze the barriers’ entry by combining the IVIFs-DEMATEL method with Choquet Integral; also, we compare the obtained results to those from the IVIFs-DEMATEL methodology. The differentiated analysis reveals that ‘Equipment Vendor Restrictions’ and ‘Lack of Awareness about Reverse Logistics’ are the main hindrances preventing local manufacturers from reaching the global space. Furthermore, the findings of this study suggest that ‘Carrier Aggregation Complexity’, ‘Equipment Vendor Restrictions’, and ‘Challenge to Recycling of Plastics’ are vital factors nonconducive towards the smooth working of local mobile makers across the country. The results can help domestic policymakers to improve their decision-making while trying to find ways for the globalization of the mobile phone sector.

Hybrid fiber–THz fronthaul supporting up to 16384-QAM-OFDM with the delta-sigma modulation

With the progress of high-capacity radio access networks, ultra-dense small cells are rapidly being deployed in urban areas. As a result, the deployment of a large number of optical fibers in urban areas becomes a severe issue. In this Letter, we propose a hybrid fiber–terahertz (THz) mobile fronthaul system supporting flexible and high-order wireless signal transmission with the delta-sigma modulation. The photonic THz transmission is used as the seamless extension of fiber-based fronthaul in small cells. A 20-Gbit/s digital fiber–THz fronthaul system is experimentally demonstrated to validate the proposed scheme, with 10-km optical fiber transmission and 300-GHz wireless relay. Carrier aggregation of up to 10 40-MHz and 60-MHz 5G-new radio (5G-NR) channels at the radio carrier frequency of 3.9 GHz is reported. The design of quantization noise suppressed delta-sigma modulation enables the system to transmit orthogonal frequency division multiplexing (OFDM) modulation up to 16384 order quadrate amplitude modulation (QAM) mapping with the error vector magnitude (EVM) below 0.5%.

LTE Carrier Aggregation Deployment – From Standardization to Deployment

Purpose: The objective of this research was to investigate LTE Carrier Aggregation commercial deployment and how soon it happened after standardization finalization. Because LTE Carrier Aggregation feature was expected to be important feature there is good reason to expect its deployment for real commercial markets. Theoretical framework: The literature at time when standardization was ongoing predicted and speculated Carrier Aggregation feature as promising deployment selection. However there is room to investigate whether Carrier Aggregation happened shortly after standard specification work finalized. Design/methodology/approach: Used methodology was to gather network operators’ and equipment manufacturers’ intentions for LTE Carrier Aggregation commercial deployment purposes during and after standardization finalization. Information found from public sources where commercial deployment intentions launched by companies. Findings: The research showed that after and already before standardization finalized there were immediate intentions for LTE Carrier Aggregation deployment. Commercial trials appeared within one year and real commercial deployments appeared within two years from standardization finalization. That means soon deployments in commercial markets when considering deployment in licensed band. Research, Practical & Social implications: For future works there could be study why not LTE Carrier Aggregation solutions in unlicensed band was not successful and whether there will be changes when going towards 5G standard related deployments. Originality/value: This article is an academic contribution for innovation feature commercial deployment in telecommunications industry and investigation whether LTE Carrier Aggregation feature deployment happened as soon as expected.

LTE INNOVATION ACTIVITY – CARRIER AGGREGATION FEATURE

Telecommunications technology development need innovation generation. Often development relates improvements for data transmission rate and latency improvements on radio interface. When building new telecommunications standards where network and mobile station can communicate together irrespective of manufacturer, there is need for standardization where various technical features construct standard specifications. There is investigated LTE standard related features and whether innovation activity has been high for Carrier Aggregation feature. Measurement for innovation activity has kept standard declaration amount because expecting that companies want to get good amount of standard essentials to achieve commercial benefit with their essential portfolio. The results show that LTE Carrier Aggregation innovation activity has been high.

On the Effects of Transmit Power Control on Multi Carrier LAA-WiFi Coexistence

To meet the ever increasing data rate demand in cellular network, the 3rd Generation Partnership Project (3GPP) introduced Licensed Assisted Access (LAA) with Listen Before Talk (LBT) mechanism to utilize the unlicensed spectrum to supplement the licensed LTE users. However, this leads to interference to already incumbent technologies in unlicensed spectrum such as WiFi. Furthermore, multi-carrier aggregation has been proposed to further increase the capacity in unlicensed spectrum. As WiFi primarily works on the principle of energy detection in the channel, in this paper, we first develop an analytical model to measure the performance of LAA and WiFi coexistence in unlicensed spectrum which supports multi-carrier aggregation which employs SINR based collision that allows the possibility of concurrent transmissions. Further, to reduce the interference to WiFi, we propose a coexistence method named Carrier Aggregation with Transmit Power Control (CATPC) which dynamically adjusts the LAA transmit power. CATPC provides a better opportunity for WiFi devices, better channel utilization, and energy efficient transmission by LAA. Through extensive simulations we demonstrate the effectiveness of CATPC when compared to other coexistence methods proposed in the literature.

Load Based Carrier Aggregation Algorithm for LTE Advanced

Long Term Evolution (LTE) supports transmission bandwidth upto 20MHz. Nowadays the multimedia rich applications connects billions of users worldwide. These services demands more number of Resource Blocks (RBs) to satisfy the Quality of Service (QoS) requirements and that can increase the data traffic in multifold. This crunch has led the Mobile Network Operators (MNOs) to increase the transmission bandwidth in order to fulfil the QoS requirements of the different services. In Release10, Third Generation Partnership Project (3GPP) provides a provision for MNOs to use Carrier Aggregation (CA) scheme in LTE-Advanced to aggregate upto five Components Carriers (CCs) of existing LTE carriers at the eNB to increase the transmission bandwidth upto 100MHz. Further, this scheme allows a User Equipment (UE) to transmit and receive data packets simultaneously on multiple CCs based on UE capability to meet the service requirements. However, the CC selection and efficient RBs utilization plays a vital role to optimize the system performance. Hence, in this paper using QualNet 8.2 network simulator the Load Based Carrier Aggregation Algorithm (LBCAA) is proposed for LTE-Advanced to aggregate the CCs of the existing LTE carriers at the eNB based on cell load in order to increase the transmission bandwidth to handle the data traffic growth. The simulations results illustrated that the proposed LBCAA for LTE-Advanced outperforms in the achieved average unicast received throughput, average unicast end-to-end delay and jitter as compared to LTE.

A survey on downlink–uplink decoupled access: Advances, challenges, and open problems

The emergence of new uplink (UL) intensive applications, coupled with the ambitious vision of the Internet-of-Things (IoT), will soon unleash unprecedented increases in UL wireless data traffic. However, current network designs are mainly concerned with optimizing the downlink (DL) performance, hence cannot give full play to UL communications. Exacerbated by high path-loss and low UL to DL duration ratio in the 5G new radio time division duplex (TDD-NR) spectrum, the UL capacity is much smaller than that of the DL one. To overcome such a problem, a DL–UL decoupled access (DUDe) approach has been proposed, in which the users are allowed to connect to different base-stations (BSs) at different frequency bands in each link direction. Moreover, DUDe can be an add-on to many 5G (and beyond) technologies, such as millimeter-wave communication, multi-connectivity, device-to-device (D2D) communication, cellular-enabled unmanned aerial vehicle (UAV) communication, and mobile edge computing (MEC). However, despite the apparent consensus on its advantages, the realization of DUDe in 5G networks is in its infancy and still requires more efforts from both academia and industry. This survey provides a holistic overview on the DUDe approach, including operating bands DUDe (i.e. supplementary UL) and serving BS DUDe, reviews its fundamentals and explores potential use-cases. Other 5G UL coverage enhancement technologies, such as UL carrier aggregation, evolved universal terrestrial radio access-new radio (EUTRA-NR) dual connectivity (EN-DC), and UL Tx Switching are also compared with DUDe. Lastly, cutting edge research works in this area are summarized along with a discussion on the potential challenges and open research problems.

A Dual-Channel High-Linearity Filtering-by-Aliasing Receiver Front-End Supporting Carrier Aggregation

A filtering-by-aliasing (FA) receiver front-end based on a slice-based time-varying architecture was described by Bu and Pamarti (2021). Unlike prior FA architectures, it demonstrated, using a 28-nm CMOS prototype IC, a time-invariant input impedance that enables dual-channel operation with high linearity. Up to 50-dB stopband rejection with a transition bandwidth (BW) of only 3.2 times the RF BW, out-of-band IIP <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> of +35 dBm, blocker 1-dB compression point of +12 dBm, and local oscillator (LO) leakage power better than −81 dBm were achieved, using a 0.9-V supply. This article elaborates on the design of this prototype, presents detailed analyses of the slice-based architecture, and shows how it addresses many of the prior FA receivers’ problems.